Grinding machine



' Jan. l5 1924. 1,480,778

c; L crT GRINDING MACHINE Fiied July 19, 1920 8 sheets-sheet 1 illy: 'l

Jan. 15 1924.. v

1 ,480,778 c. l.. o'rr GRINDING MACHINE mFiled July 19 1920 8 Sheets-Sheet 3 C. L. OTT

GRINDING MACHIN E u Filed July 19 1920 8 Sheets-Sheet 4 Jan. 15 1924- c. oTT

GRINDING MACHINE Filed July 19 1920 8 Sheets-Sheet 5 Jan. 15, 1924. y' 1,480,718 f C. L, OTT

GRINDING MACHINE Filed July 19, 1920 8 Sheets-Sheet 6 Jan. 15, 1924,

C. L.. OTT

GRIN-DING MACHINE 8 Sheetssheet 7 Filed July 19 I Jan. 15, 1924.l 1,480,778

l c. OTT l GRINDING MACHINE F'iled July 19, 1920 8 Sheets-Sheet 8 Patented Jan. 15, 1924.

uNiTED vSTATES y ,1,480,718 PATENT OFFICE.

CONRAD L. OTT, OF CHICAGO, ILLINOIS, ASSIGNOR TO AMERICAN GRINDE COMPANY, OF DETROIT, MICHIGAN, A CORPORATION F MICHIGAN.

@BINDING MACHINE.

Application filed July I9, 1920. Serial No. 397,323.

To all w/wm t may concern Be it known that CONRAD L. Orr, a citizen of the United States, and a resident of the city of Chicago, county of Cook, and State of Illinois, has invented an Improvement in Grinding Machines, of which the following is a specification.

This invention relates to machines oruse in grinding metal shafts, cylinders and the like, and is intended to provide certain improvements contributing to simplicity of design, practicability and eiiiciency of construction, and convenience of control.

The character of the invention will be best understood by reference to one illustrative device containing an embodiment of the invention which is shown for example in the accompanying drawings.

In the drawings: Fig. 1, is a front elevation of a grinding machine embodying my invention.v

Fig. 2 is an end elevation of same. Fig. 3 is a front elevation partly in sec tion and having certain parts broken away to show the head stock driving mechanism. Fig. 4 is an enlarged detail sectional view of a portion of the head stock driving mechanism. v

Fig. 5 is an end elevation of the parts shown in Fig. 4.

Figs. 6, 7, 8, and 9 are detail views of the mechanism for transmitting motion to the 4 work supporting carriage.

Figs. 10 and 11 are details of the mecha' nism employed for reversing the travel of the carriage.

Fig. 12 is an end elevation of Fig. 11.`

Figs. 13, 14, and 15 are detail views of the means for controlling manually and automatically the position ofthe grinding Wheel.

Fig. 16 is a'diagrammatic sectional view illustrating the trains of gearing for transmitting motion to the work supporting carriage and to the head stock.

Fig. 17 is a sectional elevation taken as indicated bythe line 17-17 of Fig. 9.

The grinding wheel 1 of the illustrative machine is secured removably to one end of a shaft 2 mounted to rotate in bearings 3 carried by a wheel-base 4, the latter being adapted to be moved automatically and manually toward and from the Work by mechanism hereinafter to be more fully described. To the opposite end of the shaft 2 is secured removably a pulley 5 and around said pulley, and a pulley 6 on a motor shaft V7, is trained a belt 8 for driving thegrinding Wheel, the proper degree of tension of the belt being maintained, regardless of the position of the grinding Wheel, by anidler pulley 9 in contact with the belt. If desired, a countershaft, driven by a single belt from a line shaft maybe used in lieu of the motor shaft 7 Obviously, the mountingvof the grinding Wheel 1 and pulley 5 on opposite ends of the shaft 2 facilitates the removal and the substitution of wheels or pulleys of different diameters for the purpose of varying the peripheral speedof the grinding wheel or to keep the peripheral speed of the wheel constant as its diameter decreases by Wear. This arrangement furthermore equalizes the load or thrust on the grinder shaft bearings.

The work to be operated upon is held in position between centers 10 and 10a of the head and tail stocks 11 and 12 respectively, longitudinally adjustably mounted on a swivel table 13, which in turn is mounted on a reciprocating carriage 14 in a manner to be adjusted angularly with reference thereto.

The swivel tab1e`13 is shown connected to 4the carriage 14 b a central pivot stud 13, and the said tab e is secured in desired position on the carriage Aby' clamps 13b at the respective ends of the table.

' The head and tail stocks may be longitudinally adjusted on the table by means of pinions 11a and 12a carried by the head and tail stocks respectively and engaging the usual racks 13c on the table;- said pinions having square ended shafts for engagement by an operating crank or key.

During rotation of the work which is effected by novel head-stock, driving means presently tov be described, a relative movement between the work and 'the grinder, in a direction longitudinally of the work, is effected by longitudinal .reciprocation of the carriage 14 and parts carried thereby, by an arrangement ofmechanism hereinafter to be described.

In machines' of the present class, it is desirable to rotate the work 'by a -direct belt drive in order to Vavoid the chattering incident to a gear drive of the Work-rotating means, and to .prevent uneven finish on the work; on the other hand it is undesirable to employ an overhead belt drive, and especially from a drivin source not contained 'Within the machine itself, such as for 1nstance an overhead shaft.

head stock; the construction and arrangebelt drive with the head stock.

ment of the belt drive and the actuating mechanism therefor being such. as to avoid objectionable complexities or extensions of shafting or other parts from the end of the machine, as Well as to avoid objectionable slotting of the carriage and swivel table for the belt drive, while at the same time allowing the back and forth reciprocation of the Work and adjustment of the head stock for different lengths of work.

For this purpose, the head stock is equipped withvvork-rotating means driven by a belt directly from a longitudinal shaft 23 (Fig. 3) which is actuated by mechanism contained Within the machine base; the shaft connection between said actuating mechanism and the belt drive for the Work-rotating means being such as to permit the longitudinal reciprocation of the In the illustrative. machine shown in the drawings, the shaft 23 is a sliding shaft, and is desirably arranged at the front ofthe machine i. e., at the side of the machine opposite from the rotating grinding Wheel, whereby the belt drive for rotating the Work is arranged laterally and'with respect to the Work, at the side of the machine free from obstruction bythe grinding Wheel and other parts. Said sliding shaft 23 is preferably encased in a protecting case, for which reason it is not visible in Fig. 1; but it is shown in Figs. 2 and 3,' the said protecting case being omitted in these figures.

As shown in Fig. 2, a pulley 15 is operatively connected to the head stock 11, and around said pulley and a `drive pulley 16 on said shaft 23 and idle pulleys 17 and 17, is trained a belt 18 Whereb the head stock is belt-driven from the a oresaid longitudinal shaft 23, as also clearly appears in Fig. 3 of the drawings. The proper tension of the belt 18 is'maintained by the pulley 17 mounted on a block 19 adapted to slide in Ways in a casting 2O rigidly secured to the head stock support, and adjusted and held in position by a hand crank and screw 21, the latter being threaded into the block. j

The said sliding shaft 23 has its rear end portion 22 journaled in a bearing in the lower end of the head stock casting 20, but secured against longitudinal movement in said bearing, so that the shaftl 23 will move longitudinally with the head stock. The shaft may vbe held against longitudinal movement in said casting by means of a shaft collar at one side of the casting and the pulley 16 at the other side.

The construction of the illustrative machine shovvnl in the drawings is such that the swivel table 13 together with the head and tail stocks mounted thereon may, if desired, be angularly adjusted to present the Work more or less obliquely to the line of travel of the carriage, for the purpose of formin a taper on or removing a slight taper from the Work. In view of the specific construction of the table and-head stock of the illustrative machine, the shaft is shown provided adjacent to the pulley :16 with -a universal joint connection 24 between 'the end portion 22 and the main por tion of said shaft23, so as to permit of such angular adjustment of the head stock; but it will be understood that features of; the present invention may be embodied in a construction in which the shaft 23 may be rigid, or, in other Words, that the universal joint or provision for flexing in the shaft 23 of the illustrative machine is not essential to the main features of the invention thus far described.

The work While being operated upon is moved across the face of the grinding Wheel by the reciprocation Aof the carriage 14 on Ways 25 of the mainframe or base 26. To permit of such reciprocation without interfering With the continuous drive of the head stock and Work, the shaft 23 is provided with a spline throughout its length adapted to receive a spline ykey `operatively connected to gears 27 and 28 suitably mounted and held against longitudinal movement on the gear case or cover 26a.

As shown more clearly in Figs. 4 and 1.6, the gears 27 and 28 may be driven at various speeds by gears 29 and 30 respectively, the latter gears being adapted to be clutched ,to or unclutched from a shaft 31 by a sliding clutch collar 32 actuated by manipulating` a hand-lever 33. See Figs. 4 and 5.

The shaft 31 may be driven at various speeds by a set of variable speed gears indicated as a Whole by 34, loose on the shaft and adapted to be secured individually' thereto by a sliding key 35, engaging radial slots 36 in the inner face of said gears. As shown in Figs. 4 and 5, the position of the key 35 may be controlled by the operator through a handle 37 on a stub shaft 38 to which is also secured a shipper arm 39, on the upper end of which is an anti-friction roller 40 engaging an annular groove in a sliding collar 41 having, connected thereto one end of an extension of the key 35.

By reason of the gears 29 and 30 being of different diameters and the ability to clutch one or the other to the shaft 3l to drive their respective cooperating gears 27 and 28, in

conjunction with the variable speed gears 34, it 1s obvious that the shaft 23 may be driven meedere at a plurality of speeds equivalent to twice the number of gears comprising the variable speed set.

The gears 34 are driven by a set of gears 42 of different diameters secured to a shaft 43 suitably mounted to rotate in bearings in the gear case 26a. To said shaft 43 is also secured a. double faced pulley 44. As shown in Fig. 2, the pulley 44 is driven by a belt 45 trained around the said pulley and a pulley 46 in the present instance, on the motor shaft 7.

The set of gears 42, which if desired may be a stepped gear casting, may for convenience be referred to as a master gearing, typifying a gearing from which a mechanism or mechanisms of the machine (e. g. 'the mechanism for rotating the sliding shaft 23) is driven.

lt will be noticed that in the illustrative machine the pulley 44 for operating the set of differently sized driving gears 42 is belt driven from the same source as the grinding wheel, i. e. from the motor shaft 7, which shaft carries a tivo-step pulley comprising the parts hereinbefore referred to as 'the pulleys 6 and 46 respectively.

To transmit motion to the reciprocating carriage 14 and parts mounted thereon, the mechanism now to'be described is employed. As shown in Fig. 16, a shaft 47 is mounted to rotate in the gear case, said shaft 47 having loosely mounted thereon a set of variable speed gears indicated as a whole by 48.

,These gears are adapted to be secured individually to the shaft-47 by a sliding key 49 and driven by the step gears 42 in the same manner as above described with reference to the variable speed gear set 34. The position of the key may be controlled by the operator through a. handle 50 on a shaft 51,

shown 'in Figs. 11 and 12. To said shaft is also secured a shipper arm 52 at the lower` end of which is an anti-friction roller 53 engaging an annular groove in a sliding collar 54'having connected thereto one end of an extension of the'key 49.

Referring to Fig. 16: To the shaft 47 are secured rigidly, pinions 55 and 56, the former meshing with and driving a gear 57 loosely mounted on a shaftl 58, and the flatter (pinion 56) meshing with and driving an intermediate pinion 59 (Fig. 10)

through which a gear 60 also loose on the shaft 58 is driven in the opposite direction to the gear 57. The gears 57 and 60 may be secured to the shaft 58 by a sliding clutch collar 61 keyed to and adapted to slide on the shaft 58.

Still referring to Fig. 16; To the shaft 58 is secured rigidly a pinion 62 which meshes with and drives a gear 63 loosely mounted on a shaft 64 and adapted to be secured thereto by a clutch collar 65 slidably keyed to said shaft. A worm 66 secured rigidly to the shaft 64 meshes with and drives a worm wheel 67 (Figs. 6, 9 and 16) keyed to a cross-shaft 68 which through a sliding clutch collar 69 (Fig. 9) drives a pinion 70 loosely mounted on said shaft as best shown in Fig. 9, the pinion 70 meshes with a toothed rack 71 on the under side of the reciprocatingcarriage 14l and through this connection drives the carriage in one direction cr the other depending upon which of the' two gears 57 `or 60 is clutched to the shaft 58 by the sliding clutch collar 61.

For automatically reversing the reciprocating movement of the carriage 14, the clutch collar 61 is shifted alternately into engagement with the gears 57 and 60 by a forked arm 72 egaging the annular groove in the collar. Referring to Figs. 11 and 12 the forked arm is secured to one (the lower) of a pair of parallel rods 78-73 fastened together at their ends by links 74-.74, said rods being mounted to slide in the gear case. Slidably mounted on the other or upper parallel rod is an annularly grooved collar 75 on opposite sides of which and encircling the said rod are coiled springs 7 6-7 6. Secured to the rod at the outer ends of the springs are collars 77-77 against which the springs bear and which are adapted to be engaged by latches 78-78 pivotally mounted on the gear case. To actuate the clutch 61, a shipper arm 79 having a forked lower end engaging the annular groove in the collar 75 is secured to one end of a shaft 80 mounted to oscillate in the gear case and at the opposite end of said shaft is secured an upwardly extending arm 81 provided at its upper end with a laterally extendingtubular portion 82 in which is slidably mounted a plunger 83. Adjustably mounted on the side of the reciproeatin carriage 14 is a pair of stops or dogs 84 a apted to engage the protruding end of the plunger 88 on opposite sides, as the carriage approaches the respective limits of reciprocation, thus causing the shaft to oscillate in its bearings and the forked end of the arm 7 9 to shift the collar 75, compressing one of the springs 76 until one of the proJections or fingers 85 on the arm' 79 engages and lifts the long arm of the latch 78 releasing the collar 77 and permitting the tension of 'the compressed spring to shift the rods 73 andarm 72, toca-use a rapid engaging of the teeth on the clutch collar 61.

ln the event that it is desirable for any reason to permit the carriage to pass the point determined by the position of either of' the dogs 84, it is only necessary that the operator withdraw the plunger 83 from the path of the dogs, thus permitting them to pass without adecting the reversingmechanism just described.

To permit moving the carriage manually, the motive power may be disconnected therefrom by manipulating a lever 86 (Figs. 6

through the worm 66, worm wheel 67, shaft- 68, clutch collar 69, gear and rack 71 to the carriage.

To permit the carriage to pause for a variable period of time at the end of each stroke, the clutch collar 69 is provided as shown in Fig. 9 with a stepped tooth 69a of Ivarying dimensions in width annularly adapted to engage the teeth 7 0a on the gear- 70 (Fig. 17). to rotate the latter in one direction or another depending upon the position of the clutch collar 61. The clutch collar 69 can be moved longitudinally along the shaft 68 by a forked arm 98 engaging the annular groove therein and mounted at one end of a rod 99 slidably mounted in the gear case. The ,stepped tooth 69a and teeth 70a of the gear 70 allows a lost motion between' the clutch collar 69 and said gear 70, to provide for a pause of the carriage, and by longitudinal adjustment of said collar the extent of the lost motion may be varied for varying the period of the pause. The construction shown in Fig. 9 permits this adjustment to be made while the machine is in motion.

Obviously, when the narrow portion of the tooth 691B is in position to engage the teeth 70a, the length of the pause will be greater than when the wider portions are in position to engage the teeth, thus, the position of tooth 69a with reference to the teeth 70a will determine the length of pause of the carriage 14 at the end of its stroke. before starting on its return movement.

The rod 99 is provided with notches 99a adapted to be engaged by a spring actuated ball 100 to secure the clutch collar 69 releasably in adjusted position.

To automatically feed the grinding wheel toward the work, the wheel-base 4 (Fig. 15)

Encircling the said (Fig. 13 and 14) at the lower end of which is mounted pivotally a horizontalll extending arm 107. At the outer end o the arm 107 is mounted pivotally a pawl 108 adapted to engage the teeth of the gear 105 and to rotate the latter when the arm 107 .is rocked downwardly about its pivot.

The arm 107 is held normally in its .raised position by a coiled spring 109, acting between a portion of the bracket 106 and a head 110 on the upper end of a rod 111 passing through the spring-and connected at its lower end to the arm 107. The extent of the upward movement of the arm 107 is determined by an adjusting screw 112.

Forming a part of the arm 81 and extending downwardly from the shaft is an arm'113 having secured to its lower end a laterally extending doublefaced cam stud 114 adapted to engage an anti-friction roller 115 on the arm 107. l

Thus it will be seen, that when the' upwardly ext-ending arm 81 is rocked from side to side by contact of the dogs 84 (Fig. 11) with the sides of the protruding end of the plunger 83 mounted in the upper end of said arm, the arm 107 will be forced downwardly carrying with it the pawl 108 in engagement with the teeth of the gear 105 causing the shaft 104 to' rotate and through its (onnection with the shaft 102 draw the wheel base and grinding wheel toward the work each time the movement of the carriage 14 is reversed. To enable the operator to adjust the grinding wheel to permit a predetermined degree of operation on the work, an annular collar 116 is mounted rotatably on a shoulder 117 formed on the gear 105.

Mounted. to rotate in said collar is a shaft 118 secured to one end of which is a pinion 119 meshing with the larger portion of a double pinion 120 also mounted in said collar, the smaller .portion of said double pinion meshing with the gear 105. To thel opposite or outer end of the shaft 118 is secured an arm 121 carrying at it outer end a detent 122 adapted to engage any one of a plurality of holes in a plate 123 secured to the collar 116. Y

Formed on the collar 116 is a stop shoulder 124 and a finger 125. The former is adapted to engage a sliding stop pin 126 mounted on the gear case. and the latter to pass between the tooth engaging end of the pawll 108 and the teeth of the gear 105 thus rendering the pawl inoperative. The operator may while the detent 122 is in engagement with one of the holes in the plate 123, place the grinding wheel in any desired position by manipula-ting a hand crank 127 mounted en the collar 116, and then, by disengaging the detent and rotating the shaft 118 may rotate the annular collar relative to the 'gear 105 and position the stop shoulder 124 the y,desired distance from the stop/pin 126 and again engage the detent, locking the collar 116 and gear 105 together.

When power is applied to the machine, the pawl 108 willv intermittently move the grinding wheel toward the Work until the stop shoulder 124 engages the stop in 126 and the finger 125 renders the pawls inoper-l ative.

If after the limit of the automatic feed has been reached, it is desired to move the grinding wheel further, the stop pin 126 may be withdrawn from` the path of the stop shoulder and the gear 105 rotated manually.

To supply a flow of water atthe point of contact between the grinding wheel and the work, a ,tank 127a is provided, from which the water is drawn by a rotary pump 128 and forced through a tube 129 to a nozzle, 130, the flow of the water being controlled by a shut-of-cock 131. tSee Fig. 2.

The pump may be driven by a belt 132 trained around the pulley 44 and a pulley 133 on the pump shaft 134 (Fig. 2). Y

It will be observed that with the exception of the grinding wheel drive, all of the driving and controlling mechanism is mounted on the gear case or cover 26a, thus providing a simple construction whereby all of these elements may be' assembled as a unit, which, when secured'Y in place on the base or main frame 26, necessitates only the connecting of the shaft 23 to the shaft 22 throu h the coupling 24 (Fig. 3) and the threa ing of the -nut 103 on to the shaft 102 l5) to render the grinding machine rea y'for operation.

The illustrative machine is `self-contained in that none of the parts are driven from separate pulleys on an over-head shaft or the like, but the grinder- Wheel and mech'- -anism for rotating and reciprocating the" work are driven from a common source, for instance, from the shaft of a motor conveniently applied atI one end of the machine. The machine is of practicable construction and of relative simple design and embodies desirable advantages in operation, among which are smooth operation of the work by the belt drive, which is accomplished Without complex mechanism.

Obviously the present Iinvention is not limited to any particular form of construction and the details of the illustrative construction may be variously modified. Moreover, it is not indispensable that all the features of the invention be used conjointly as they may be used to advantage in variousl different combinationsv and sub-combinations.

I claim- 1. A grinding machinev having, in combination, traveling work-supporting means; a grinder for operating on the work; beltdriven means for rotating the work; a

traveling belt drive for said Work-rotating means, including a driving pulley therefor;

ing pulley constructed and arranged to per-A mit said pulley and belt-drive to travel with the work. 2. A grinding machine having, in combination, means for reciprocating the work; a grinder for, operatin on the work;a1ong'i tudinal shaft arrange on the opposite side of the machinefrom the grinder; means for rotating said shaft; a belt-driving ulley on said shaft; and belt-driven means riven from said pulley for rotating the work; the construction and arrangement being lsuch as to permit the said belt-driving pulley and belt-driven means to move to and fro with the work.

3. A grinding machine having, in combination, traveling work-supporting means; a grinder for operating on the work; a longitudinal shaft; shaft-driving means including a gear on said shaft; a belt-.driving pulley on said shaft and operated thereby; said shaft having a sliding it in one of the said elements thereon to ermit said belt-driving pulley to travel wit the work; and a belt driven by said pulley and belt driven means for rotating the work, said pulley belt and belt-driven means traveling with the' work.

4. A grindin machinehaving, in combination, travelmg work-supporting means;

a grinder for operating on the work; a longibination, a .reciprocatory carriage; head and tail stocks thereon; a grinder; beltdriven work-rotating means carried'by the head stock; a longltudinal sliding shaft;

shaft-driving means constructed and arranged to permit the shaft to slide; and a driving-pulley on said slidin shaft for driving the'belt of said beltriven workrotating means.

6. A grinding machine having, in combination, a reciprocatory carriage for moving the work longitudinally; head and tail stocks thereon; a grinder for operating on the work; a belt drive and belt-driven means carried by the head stock for rotating the work; actuating mechanism housed in the machine base toward the tail stock end of the machine; and a shaft connectionfrom said actuating mechanism to said belt drive for operating the latter, constructed and arranged to permit said belt drive to move longitudinally with the head stock.

7. A grinding machine having, in combination, a reciprocatory carriage for moving the work longitudinally; head and tail stocks thereon; a rinder for operating on the work; a belt drive and belt driven means carried by the head stock for rotating the Work; actuating mechanism housed in the machine base toward the tail stock end of the machine; va longitudinal slidin shaft actuated by said mechanism, sai shaft connected with the head stock to be moved longitudinally therewith; and a driving pulley for said vbelt drive on said shaft.

8. A grinding bination, a longitudinally reciprocatory carriage; head and tail stocks thereon; a grinder; a longitudinal sliding shaft at the side of the machine opposite from said grinder; shaft-driving meansV lpermitting said shaft to slide; and belt-driven Workrotating means on the head vstock driven directly from saidl sliding shaft.

9. A grinding machine having, lin combination, means for reciprocating the Work; a grinder for operating on the Work; a longitudinal shaft arranged on the opposite side of the machine from the grinder; means. for rotating said shaft;a belt-driving pulley on said shaft; and belt-driven means driven from said pulley for rotating the work; the construction and arrangement.

being such as to permit the said belt driving pulley and. belt driven means to lmoveto and fro with the work; means for angular adjustment of the work together with said belt drive; and a universal joint in said longitudinal shaft'adjacent to said belt-driving pulley.

lO. A grinding machine having, in combination, traveling Work-supporting means; a grinder for operating on 'the work; beltdriven vmeans for rotating the Work.; a traveling belt drive for said Work-rotating means, including a driving pulley therefor; actuating means housed in the base of the machine; a direct operating connection from said actuating means to `said belt-driving pulley constructed and arranged to permit' said pulley and belt-drive to travel with the Work; means for an larly adjusting the Work together with said belt drive; and said operating connection having a iexible coupling to permit such angular adjustment.

l1. A grinding machine, having in combination, a grinder; ahead stock and tail stock; the head stock being longitudinally adjustable relative to the tail stock; beltdriven work-rotating means carriedv by head stock, and a belt drive therefor, including a belt-driving pulley; and an operating shaft for said pulley at the front of the machine, arranged to permit longitudinal adjustments of the head stock.

12.A A grinding machine having, in combination, a slidable carriage; Work holding machine having, in com-A means mounted on said carriage; a grinding Wheel; a master gearing; separate sets o variable speed gears operated by vsaid-master gearing; means operated by one set of gears for reciprocating the carriage; a longitudinally sliding shaft operated by the other of said sets of gears; and belt driven means operated from said sliding shaft for rotating the work.

13. A grinding machine having, in combination, traveling Work-holding means; ai rotatable grinder; belt-driven Work-rotating means, and a driving belt and a belt-driving pulley therefor; mechanism housed Within the machine base for reciprocating the Workholding means and for operating said beltdriving pulley; said mechanism and .said grinder arranged to be belt-driven from a common source as, for instance, a motor at one end of the machine; and adjacent .belt

' drives for said grinder and said mechanism.

V14. A grinding machine having, in combination, traveling Work-holding means; a rotatable grinder; belt-driven Work-rotating means, and a driving belt and a belt driving pulley therefor; mechanism housed' Within the machine base for reciprocating 'the Workholding means and for operating said beltdriving pulley; a two-step pulley at one end of the machine; and a pair of belts driven by said two-step pulley; one of said belts operating said grinder and the other of said belts operating said mechanism.

15. A grinding machine having, in combination, a longitudinally reciprocatory carriage; head and tail stocks thereon; beltdriven Work-rotating means carried by the head stock, and a belt drive therefor; a rotary grinder; a grinder shaft having a pulley disposed near the tail stock end of the machine; operating mechanism housed Within the machine base; a pulleyI for driving said mechanism disposed near the tail stock end of the machine; a pair of adjacent belts for driving said grinder shaft pulley and said driving pulley for said mechanism;

means operated by said mechanism for reciprocating the carriage; and means operated by said mechanism for operating said .belt drive of said belt driven Work rotating means.

16. A grinding machine having, in combination, a slidablecarriage; Work holding means mounted on said carriage; belt-driven Work-rotatingv means, and a driving belt therefor; a grinding Wheel; a master gearing; separate sets of variable speed gears operated by said master Vgearin means operated by one set of said gears or operating said belt drive for rotating the Work, said means constructed and arranged to permit the belt drive to travel With the Work; means operated by the other of said sets of gears for reciprocating the carriage; and adjacent meagre belt drives for operating said master gearing and said grinding Wheel from a common source.

17. A grinding machine comprising, in combination, a slidable carriage; a Workholder mounted on said carriage; a grinding wheel coopcrable with said work-holder; ,a master gearing; means for driving said wheel and said gearing; separate means driven by said gearing for rotating said work-holder and reciprocating said carriage, the latter means comprising' a shaft, aset of variable-speed gears loosely mounted thereon and adapted -to be driven by said master gearing, means for securing any one of said gears to said shaft, a pair of gears fixed to said shaft, a second shaft parallel to said Iirst shaft, a pair of gears loosely mounted thereon, carriage actuated means for securing one or the other of said last mentioned gears tosaid second shaft, one of said loose gears adapted to be driven byl one of said fixed gears, the other loose gear adapted to be driven by the other fixed gear through an intermediate gear, a gear fixed to said second shaft, a worm shaft parallel to said second shaft, a gear loosely mounted thereon Y and adapted to be driven by said last mentioned gear, means for securing said loosely mounted gear to said Worm shaft, means for manually lrotating said Worm shaft, a Worm ixed to said Worm shaft, a transverse shaft, a Worm wheel xed thereto and adapted to be driven by said Worm, a pinion loosely mounted on said cross shaft, clutch teeth on one side of said pinion, a clutch collar splined to said cross shaft, having a tooth of varying dimensions in Width annularly and adapted to cooperate with the clutch teeth on said pinion, a rack on the under side of said carriage adapted to be engaged by said pinion; and means for moving said clutch collar and tooth toward and from said pinion to bring the faces of said clutch teeth into the annular path of the various faces of the tooth on said clutch collar.

In testimony Whereof,-l[ have signed my name to this specification.

CUNRAD L OTT. 

